ind_shnorm <- function(expmeanval0,expmu, oo, sharesum, marketForProducts) {

numer<-(expmeanval0%*%oo)*expmu         # this is the numerator (oo speeds-up expanding mean utility by number of draws)
sum1<-sharesum%*%numer
sum11<-1/(1+sum1)	                      # this is the denominator of the shares
sum11<-as.matrix(sum11)
denom1<-sum11[marketForProducts,]       # this expands the denominator
SS<-numer*denom1                        # simulated shares for each draw
PROB<-rowMeans(SS) 		
PROB<-as.matrix(PROB)

return(PROB)  

}